<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <style>
        * {
            margin: 0px;
            padding: 0px;
        }
        #head{
            border: 3px solid yellow;
            width: 100%;
            background-image: url("../images/mn.png");
            background-repeat: no-repeat;
            background-position: 2px;
            background-color: aquamarine;
        }
        #head:after{
            content: '';
            clear: both;
            display: block;
            display: inline-block;
        }

        a{
            text-decoration: none;
            color: black;
        }
        a:hover{
            color: orange;
        }
        ul li{
            display: inline-block;
            text-align: center;
            line-height: 240px;
        }
        #a {
            height: 440px;
            width: 260px;
            border: 1px solid black;
            float: left;
        }
        #b {
            margin-top: 0px;
            height: 240px;
            width: 400px;
            border: 1px solid black;
            float: left;
        }
        #b ul{
            list-style-type: none;
            border: 1px solid red;
        }
        #c {
            height: 240px;
            width: 200px;
            border: 1px solid black;
            float: right;
        }
        #d {
            height: 240px;
            width: 200px;
            border: 1px solid black;
            float: right;
            background-color: bisque;
        }
    </style>
</head>
<body>
<header id="head">
    <div id="a">

    </div>
    <div id="b">
        <ul>
            <li><a href="">菜单1</a></li>
            <li><a href="">菜单1</a></li>
            <li><a href="">菜单1</a></li>
            <li><a href="">菜单1</a></li>
            <li><a href="">菜单1</a></li>
        </ul>
    </div>
    <div id="c">
        <p>如上图,现在都变成空心圆了,这是用HTML ul标签和属性组合而成的三种样式(还有一种样式是把小圆点变回来的,用的是type=“ disc”)在很多都开始用css样式表来给...</p>
    </div>
    <div id="d">
        <p>如上图,来给...</p>
    </div>
</header>
</body>
</html>